Albert j



(No Model.) A

A. J.V PITKIN.

GoMPoUND ENGINE.

Patente-d Nov; 2, 1897 me mams versus ca, prgorumofwnsnmnmw. n. c.

UNITED: STATES gPATENT OFFICE.

ALBERT J. PITKIN, OF SCHENECTADY, NEW YORK.

COMPOUND ENGINE.

SPECIFICATION forming part of Letters Patent No. 592,823, dated November2, 1897.

Application nea February 15, 1897. 4serai No. 623,392. nu, ms.)

To all whom it may cork/cern: Be it known-that I, ALBERT J. PITKIN,citizen of the United States, residing at Schenectady, in the county ofSchenectady and State of New York, have invented certain new and usefulImprovements in Compound Engines, of which the followingisaspecification.

My invention relates to compound locomotive-engines in which the` highand low pressure cylinders are connected by a receiverpipe located inthesmoke-box of the locomotive. In all such locomotive-engines asheretofore constructed condensation'of steam occurs in the high-pressurecylinder, which is carried over into the low-pressure cylinder, therebyoccasioning a loss of power. This condensed steam is not revaporated inany receiver-pipe heretofore used with which I am familiar, although itis a fact that the temperature of the gases in the smoke-box of alocomotive is very much higher than that of the steam passing throughthe receiver.

The object of my invention is to prevent the passage of the condensedsteam from the high-pressure to the low-pressure cylinder, and thusprevent the corresponding loss of power. I therefore so construct thereceiverpipe that it shall most efficiently gather the high temperatureof the gases in the smokebox and convey this high temperature to theinterior of the receiver-pipe, so that the condensed steam which passesfrom the highpressure cylinder may be arrested and evaporated and raisedto a high temperature, so`

that when it enters the low-pressure cylinder it may operate with thegreatest efficiency.

The best way now known to me of carrying out my invention is to providethe receiverpipe with a number of projections on. the outside to collectthe heat from the smoke-box and corresponding projections on the insideto convey the heat thus accumulated to the steam passing through thepipe. Preferably these projections are arranged in the form oflongitudinal parallel ribs both on the inside and the outside of thereceiver-pipe, as by this arrangement not only is the heat mostefficiently collected and conveyed, but no obstruction is offered to thefree passage of steam through the pipes, and a large surface ispresented for the radiation of heat to cause the evaporation of thecondensed steam.

I am aware that in Deans patent, No. 459,77 9, of September 22, 1891', areceiverpipe is shown in which annular or transverse projections arearranged on the outside of the receiver-pipe; but the Dean patent onlyclaims that this construction will raise the temperature of the steamcontained in the receiver-pipe, and thus increase the effectiveness ofthe low-pressure cylinder. The construction is such as to raise thetemperature of the steam to some extent, but by no means to such anextent as to cause the evaporation of the condensed steam passing fromthe highpressure cylinder.` The ribs inthe Dean patent expose'a greatersurface to the action of the gases in the smoke-box; but the interiorarrangement of the receiveris not such as to arrest the passage ofcondensed steam to the low-pressure cylinder.

I am aware, of course, that pipes for radiators, boiler-tubes, dac.,have been constructed with projections on the inside and on the outside.These have been known for many years to those constructing and operatingcompound locomotive-engines; but prior to my invention such tubes orpipes have never been utilized to overcome the very serious objectionsincident to all receiver-pipes in use prior to my invention, and it wasnot until I perfected my invention that I discovered that the efficiencyof the low-pressure cylinder could be solargely increased by arrestingthe passage of the condensed steam in the manner above stated.

In the accompanying drawings, Figure I shows a transverse sectionthrough a part of ka compound locomotive-engine with my improvementsapplied. Fig. 2 Vis a detail view showing especially the connection ofthe livesteam pipe with the vhigh-pressure cylinder, and also theconnection of the receiver-pipe with this cylinder. Fig. 3 shows atransverse section of a modified form of receiver-pipe.

The high-pressure cylinder A and the lowpressure cylinder B are mountedin any suitable way and are connected by passages a b with thereceiver-pipe C. The live-steam pipe D is connected with thehigh-pressure der in the usual way. o

The receiver-pipe C is arranged within the IOO cylinder, as shown inFig. 2, andthe exhaust E is connected with the low-pressure 'cylinshellF of the smoke-box, as usual, and this pipe is of the usualconstruction, except that it is provided with a series of longitudinalribs c on the outside and a series of longitudinal ribs d on the inside.These ribs extend from end to end of the receiver-pipe. They are arranged,preferably,radially, as indicated in Fig. 2, and the ribs on theoutside preferably aline with those on the inside. It will beunderstood, however, that so far as the broad features of my inventionare concerned other forms of projections may be employed, the essentialbroad feature of my invention being the use of projections both on theinside and on the outside of the receiver-pipe, so arranged andconstructed as to convey a suflicient amount of heatl from the smoke-boxto the interior of the receiver-pipe to evaporate the condensed steam.The curved shape of the receiver-pipe, as shown in Fig. 3, causes thecondensed steam from the high-pressure cylinder to impinge against thesurfaces of the interior projections (Z, and thus a quicker evaporationis effected.

I claim as my inventionl. The combination with the high and low pressurecylinders of a compound locomotiveengine, of the smoke-box and thecurved receiver-pipe for conveying exhaust-steam from the high-pressureto the lo\\pressure cylinypressure cylinders, the smoke-box, and thecurved receiver-pipe formed with a series of curved longitudinal ribsboth on its interior and exterior.

4. The combination of the high and low pressure cylinders, thesmoke-box, the curved receiver-pipe, and a series of curved ribs arthesurfaces of the ribs and to be rapidly evaporatedl thereby.

i l l In testimony whereof I have hereunto subscribed my name.

' ALBERT J. PITKIN. Vitnesses:

Guo. S. CLARE, WM. J. VAN AUKEN.

